The following invention as is expressed in the title of the present specification consists of coin operated telephone payment device, which has noteworthy advantages with regard to those conventionally used.
In order to make telephone calls from those conventional public telephones which operate by inserting coins, the coins can be put into an outside slot on the telephone. Upon talking, the coins pass into the money box, without the possibility of recovery by the user. In other words, payment is made prior to the conversation.
Thus, when the time corresponding to the value of the inserted coin is used up, another coin must be inserted or the call will be cut off.
This form of payment has the inconvenience for the user of public telephones that if a coin with a large value (for example 200 ptas.) is inserted and the person with whom one wishes to speak is not in and the time of the call corresponds to a much smaller value (for example 20 ptas.) the difference is not recovered.
Likewise, in other public telephones, when the user wishes to make a call, he inserts the coins which are selected and the valid ones are deposited by order of introduction in a provisional receptacle, from which they pass to a definitive receptacle as the conversation goes on. Once the conversation is over and the caller hangs up, the coins which have not been used are returned to the return box. In this case, the user has the same inconvenience cited above, since the coins go to the definitive coin box by order of introduction and value, with the cost of the call not corresponding to the time used.
In order to overcome this inconvenience and so that the cost of the call corresponds as much as possible to the coins that the user has inserted, the device of the present invention correlates the cost of the call to the coins inserted.